Coolant supply unit, cooling unit, and electronic device

ABSTRACT

A coolant supply unit includes a plurality of pumps, a casing that includes a coolant inlet port, a plurality of branch ports that respectively convey coolant to the plurality of pumps, a plurality of flow merging ports through which the coolant from the plurality of pumps merges, and a coolant outlet port; and a separating wall that is provided inside the casing and that separates the inside of the casing into a distribution chamber that is in communication with the inlet port and the branch ports, and a flow merging chamber that is in communication with the flow merging ports and the outlet port.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Divisional of co-pending application Ser. No.13/953,838 filed on Jul. 30, 2013, which claims priority to JapanesePatent Application No. 2012-197930, filed on Sep. 7, 2012. The entirecontents of all of the above applications are hereby incorporated byreference.

FIELD

The embodiments discussed herein are related to a coolant supply unit, acooling unit and an electronic device.

BACKGROUND

Structures are sometimes employed wherein coolant for cooling a heatemitting component such as an electronic component inside an electronicdevice is circulated by a pump.

It is preferable to increase the coolant flow rate in order to raisecooling performance. It is also preferable to increase the coolant flowrate when plural heat emitting components are cooled. Technology isknown in which, for example, plural pumps are coupled to liquid coolantloop tubing.

RELATED PATENT DOCUMENTS

Japanese Laid-Open Patent Publication No. 2005-315255

SUMMARY

According to an aspect of the embodiments, a coolant supply unitincludes: plural pumps; a distribution chamber portion that includes acoolant inlet port and plural branch ports that respectively convey thecoolant to the plural pumps; and a flow merging chamber portion thatincludes plural flow merging ports where the coolant from the pluralpumps merges and a coolant outlet port, and that is integrated togetherwith the distribution chamber portion to configure a casing.

The object and advantages of the invention will be realized and attainedby means of the elements and combinations particularly pointed out inthe claims.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and arenot restrictive of the invention.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view illustrating a coolant supply unit of afirst exemplary embodiment.

FIG. 2 is a side view illustrating a coolant supply unit of the firstexemplary embodiment.

FIG. 3 is a face-on view illustrating a coolant supply unit of the firstexemplary embodiment.

FIG. 4 is a perspective view illustrating a cooling unit of the firstexemplary embodiment.

FIG. 5 is a plan view illustrating a cooling unit of the first exemplaryembodiment.

FIG. 6 is a block diagram illustrating a cooling unit of the firstexemplary embodiment.

FIG. 7 is a perspective view illustrating an electronic device of thefirst exemplary embodiment.

FIG. 8 is a plan view illustrating an electronic device of the firstexemplary embodiment.

FIG. 9 is a block diagram illustrating a cooling unit of a comparativeexample.

FIG. 10 is a perspective view illustrating a coolant supply unit of asecond exemplary embodiment.

FIG. 11 is a side view illustrating a coolant supply unit of the secondexemplary embodiment.

FIG. 12 is a face-on view illustrating a coolant supply unit of thesecond exemplary embodiment.

FIG. 13 is a perspective view illustrating a coolant supply unit of athird exemplary embodiment.

FIG. 14 is a side view illustrating a coolant supply unit of the thirdexemplary embodiment.

FIG. 15 is a face-on view illustrating a coolant supply unit of thethird exemplary embodiment.

FIG. 16 is a side view illustrating plural coolant supply units of thethird exemplary embodiment in a state connected together in a row.

FIG. 17 is a perspective view illustrating a coolant supply unit of afourth exemplary embodiment.

FIG. 18 is a side view illustrating a coolant supply unit of the fourthexemplary embodiment.

FIG. 19 is a face-on view illustrating a coolant supply unit of thefourth exemplary embodiment.

FIG. 20 is a side view illustrating plural coolant supply units of thefourth exemplary embodiment in a state connected together in a row.

FIG. 21 is a perspective view illustrating a coolant supply unit of afifth exemplary embodiment.

DESCRIPTION OF EMBODIMENTS

Detailed explanation follows regarding a first exemplary embodiment,with reference to the drawings.

As illustrated in FIG. 1 to FIG. 3, a coolant supply unit 12 of thefirst exemplary embodiment includes substantially rectangular box shapedcasing 14, and plural (six in the illustrated example) pumps 16connected to the casing 14.

In the following explanation, the length direction, width direction andheight direction of the casing 14 are respectively indicated by thearrows L, W, and H. Note that the length direction, width direction andheight direction do not limit the actual installation orientation of thecoolant supply unit 12.

As illustrated in FIG. 2 and FIG. 3, a separating wall 18 thatpartitions the inside of the casing 14 into two chambers is providedextending along the casing 14 length direction and width directioninside the casing 14. In the present exemplary embodiment, theseparating wall 18 is disposed parallel to a bottom wall 20 at a casing14 height direction intermediate position. The separating wall 18separates the inside of the casing 14 into a distribution chamber 22(the chamber on the upper side in the illustrated example) and a flowmerging chamber 24 (the chamber on the lower side in the illustratedexample). In other words, the casing 14 has a structure into which adistribution chamber portion 26 that includes the distribution chamber22, and a flow merging chamber portion 28 that includes the flow mergingchamber 24, are integrated together by the separating wall 18 thatserves as a common portion. Note that in the present exemplaryembodiment, the distribution chamber 22 is positioned at the upper sideof the flow merging chamber 24, however the distribution chamber 22 mayalso be positioned at the lower side of the flow merging chamber 24.

A coolant inlet port 30 is provided to a one end wall 34 (a wall on onelength direction end portion side) of the casing 14. The one end wall 34of the casing 14 is further provided with a tank side connection tube 46that is in communication with the distribution chamber 22 through theinlet port 30.

A coolant outlet port 32 is provided to a side wall 38 of the casing 14at a position close to an other end wall 36 (a wall on the other lengthdirection end portion side). The side wall 38 of the casing 14 isfurther provided with a heat receiving member side connection tube 48that is in communication with the flow merging chamber 24 through theoutlet port 32.

Plural (in the illustrated example, three on one side wall 38, giving atotal of six for both side walls) branch ports 42 are provided to bothside walls 38 of the casing 14 at positions to the upper side of theseparating wall 18, namely at positions corresponding to thedistribution chamber 22. In the present exemplary embodiment, the pluralbranch ports 42 are provided at an equal separation in the casing 14length direction. Pump side connection tubes 50 are provided to the sidewalls 38 of the casing 14, corresponding to the respective branch ports42, and in communication with the distribution chamber 22 through thebranch ports 42.

The same number of flow merging ports 44 as the number of branch ports42 are provided to both side walls 38 of the casing 14 to the lower sideof the separating wall 18, namely at positions corresponding with thebranch ports 42. The flow merging ports 44 correspond one-for-one withthe branch ports 42. In the present exemplary embodiment, the pluralflow merging ports 44 are provided at equal separations (at the sameseparations as the branch ports 42) in the casing 14 length direction.Pump side connection tubes 52 are further provided to the side walls 38of the casing 14, corresponding to the respective flow merging ports 44,and in communication with the flow merging chamber 24 through the flowmerging ports 44.

In the present exemplary embodiment, the respective flow merging ports44 are provided at positions displaced in the casing 14 length directiontowards the one end wall 34 side, or towards the other end wall 36 side,with respect to the corresponding branch ports 42.

The plural pumps 16 are disposed at the sides of the casing 14. Each ofthe pumps 16 includes an inlet tube 54 and a discharge tube 56.Connection tubes 58 respectively connect the inlet tubes 54 to the pumpside connection tubes 50, and the discharge tubes 56 to the pump sideconnection tubes 52. Coolant in the distribution chamber 22 canaccordingly be first fed into the pumps 16, and then pressurized andconveyed towards the flow merging chamber 24 by the drive of the pumps16.

In particular in the present exemplary embodiment, the correspondingbranch ports 42 and flow merging ports 44 are provided at positionsdisplaced from each other in the casing 14 length direction. In sideview of the casing 14, a length direction L1 of the respective pumps 16is accordingly inclined at a specific angle of inclination with respectto a length direction L of the casing 14.

As illustrated in FIG. 4 and FIG. 5, a cooling unit 72 of the presentexemplary embodiment includes the coolant supply unit 12, a heatreceiving member 74, a heat exchanger 76, and a tank 78. In theparticular example illustrated in FIG. 4 and FIG. 5, plural (two) of thecoolant supply units 12 are provided, however, configuration may be madewith a single coolant supply unit 12, as in the example illustrated inFIG. 6.

In the present exemplary embodiment, the heat receiving member 74 isformed in a substantially plate shape. Coolant is able to move insidethe heat receiving member 74. As illustrated in FIG. 6, electroniccomponents 80 and a power supply component, serving as examples ofcooling target members, are disposed below the heat receiving member 74.In the particular example illustrated in FIG. 6, the heat receivingmember 74 is positioned above the electronic components 80 that aremounted on a board 96.

A connection tube 82 connects the heat receiving member 74 to the outletport 32 of the casing 14 through a clip 83 and the heat receiving memberside connection tube 48. A connection tube 84 connects the heatreceiving member 74 to an external member. Heat from the electroniccomponents 80 (see FIG. 6) and the power supply component that arecooling target members is absorbed by the coolant when coolant suppliedfrom the coolant supply unit 12 passes inside the heat receiving member74, thereby cooling the cooling target members. The coolant with raisedtemperature due to the heat of the cooling target members is expelledthrough the connection tube 84 to the external member.

Note that the external member may be another heat receiving member, ormay be the heat exchanger 76. However, construction is such that coolantthat moves to another heat receiving member subsequently moves to theheat exchanger 76.

As illustrated in FIG. 4 and FIG. 5, the heat exchanger 76 is disposedwith length direction matching the orientation of the casing 14 lengthdirection (the arrow L direction) in plan view. The tank 78 that isconnected to the heat exchanger 76 is disposed with length directionoriented intersecting (orthogonally in the illustrated example) with theheat exchanger 76 in plan view. Namely, as seen in plan view, the heatexchanger 76 and the casing 14 are parallel to each other, whilst boththe heat exchanger 76 and the casing 14 are disposed at an orientationorthogonal to the tank 78. Moreover, at least one (three in theillustrated example) of the plural pumps 16 is disposed between the heatexchanger 76 and the casing 14 positioned adjacent thereto.

The heat exchanger 76 is an example of a cooling member, and cools thecoolant with raised temperature in the heat receiving member 74. Thecooling member is not limited to the heat exchanger 76 provided that thecoolant can be cooled.

The tank 78 is an example of a storage member, and temporarily storescoolant that has been cooled in the heat exchanger 76 that is partwaythrough being conveyed to the coolant supply unit 12. Note that afunction to remove a gas component from the temporarily stored coolantmay also be included.

As illustrated in FIG. 7 and FIG. 8, an electronic device 92 of thepresent exemplary embodiment includes a substantially rectangular boxshaped case 94. The board 96 is housed inside the case 94. Theelectronic components 80 (see FIG. 6) that are cooling target membersare mounted on the board 96. The electronic components 80 are positionedbeneath the heat receiving members 74.

Plural sockets 102 are mounted on the board 96. Integrated circuits,configuring for example memory, are attached to the respective sockets102. The cooling unit 72 and the sockets 102 are disposed over the board96 in shapes and positions that do not impinge on each other.

Cooling fans 98 that introduce cooling air from the outside are disposedinside the case 94. Cooling air introduced into the case 94 by thecooling fans 98 contacts and cools the heat exchanger 76 and theelectronic components 80.

Next, explanation follows regarding operation of the coolant supply unit12, the cooling unit 72 and the electronic device 92 of the presentexemplary embodiment.

In the cooling unit 72 of the present exemplary embodiment, coolant isconveyed by drive of the plural pumps 16 from the flow merging chamber24 of the coolant supply unit 12 to the heat receiving member 74. Theelectronic components 80 are cooled by the coolant in the heat receivingmember 74 taking away the heat of the electronic components 80, and thetemperature of the coolant rises. The coolant is then cooled in the heatexchanger 76, and stored in the tank 78. When the pumps 16 are drivencontinuously, the coolant is conveyed to the distribution chamber 22 ofthe coolant supply unit 12. The coolant then passes the pumps 16 and isconveyed out into the flow merging chamber 24. Namely, a coolantcirculation loop 100 is configured wherein the coolant returns to thecoolant supply unit 12 after passing from the coolant supply unit 12through the heat receiving member 74, the heat exchanger 76 and the tank78.

As can be seen from FIG. 1 to FIG. 3 and FIG. 6, the coolant supply unit12 of the present exemplary embodiment includes plural of the pumps 16.A high coolant flow rate (the amount of coolant that can be supplied pertime unit) can accordingly be secured even when the respective pumps 16are small in comparison to a coolant supply unit 12 including a singlepump. High cooling performance can moreover be maintained even when alarge number of cooling target members (such as the electroniccomponents 80 in the exemplary embodiment described above) are disposedin the electronic device 92, due to securing a high coolant flow rate.

In particular, the cooling unit 72 has high cooling performance of forexample the electronic components 80 even when the amount of generatedheat increases due to higher performance and higher density mounting ofthe electronic components 80 in the electronic device 92.

Moreover in the present exemplary embodiment, when a low coolant flowrate is sufficient, a portion of the plural pumps 16 may be driveninstead of driving all of the plural pumps 16. Namely, since there areplural of the pumps 16, there are high degrees of freedom for varyingthe coolant flow rate, since cases in which a low coolant flow rate issufficient can be easily accommodated by driving a portion of the pumps16.

Energy consumption (drive power) can also be suppressed when a portionof the pumps 16 are driven compared to when all of the pumps 16 aredriven. Since there are plural of the pumps 16 in the present exemplaryembodiment, even when for example the performance of a portion of thepumps 16 drops, this drop in performance can be compensated for by theother pumps 16.

Note that for example a single large pump and an increased total amountof coolant inside the coolant circulation loop might be considered inorder to secure a high coolant flow rate. However, were such aconfiguration to be adopted, not only would the pump increase in size,but the capacity of the tank would also increase, resulting in a largercooling unit. There would also be low degrees of freedom for varying thecoolant flow rate, since there is only a single pump. Moreover, thecoolant supply performance of the overall cooling unit would drop with adrop in the performance of the pump.

FIG. 9 illustrates a cooling unit 202 of a comparative example. Thecooling unit 202 of the comparative example does not include the coolantsupply unit 12 of the above exemplary embodiment, and is merely providedwith plural pumps 206. Note that in FIG. 9, elements similar to thoseillustrated in FIG. 6 are allocated the same reference numerals.

In the cooling unit 202, a tank 208 is disposed on the coolantcirculation direction upstream side of the plural pumps 206. Heatreceiving members 210 are disposed on the coolant circulation directiondownstream side of the plural pumps 206. Multi-branched tubes 212 areprovided between the tank 208 and the plural pumps 206, splitting thecoolant flow path from the tank 208 to the respective pumps 206. A flowmerging tube 214 that merges the coolant conveyed out from therespective pumps 206, as well as for example multi-branched tubes 216that distribute the coolant to the plural heat receiving members 210,are provided between the pumps 206 and the heat receiving members 210.Namely, the cooling unit 202 of the comparative example comprises acomplicated structure of multi-branched tubes and flow merging tubes,leading to concerns regarding increase in size of the cooling unit 202.

However, in the cooling unit 72 of the present exemplary embodiment, thedistribution chamber portion 26 and the flow merging chamber portion 28are integrated together in the coolant supply unit 12. In other words,the separating wall 18 provided inside the single casing 14 separatesthe inside of the casing 14 into the distribution chamber 22 and theflow merging chamber 24. The cooling unit 72 of the present exemplaryembodiment accordingly does not comprise multi-branched tubes or flowmerging tubes such as in the comparative example. The cooling unit 72 ofthe present exemplary embodiment is therefore simpler in structure thatthe comparative example, and can be made more compact. The electronicdevice 92 provided with the cooling unit 72 of the present exemplaryembodiment is also simpler in structure than an electronic deviceprovided with the cooling unit 202 of the comparative example, and canbe made more compact.

By integrating together the distribution chamber portion 26 and the flowmerging chamber portion 28 as described above, the coolant supply unit12 can also be made more compact than a structure wherein thedistribution chamber portion 26 and the flow merging chamber portion 28are provided as separate bodies.

In particular, depending on the type of the electronic device 92, pluralintegrated circuits (for example a CPU) may be mounted on the board 96as the electronic components 80. Such an electronic device 92 calls forhigh performance cooling of the plural integrated circuits. In thepresent exemplary embodiment, the coolant supply units 12 in the coolingunit 72 are added or removed as units, thereby adjusting the coolingperformance with ease.

Coolant supply performance can also be varied by adding or removingcoolant supply units 12 even when the number or placement of theelectronic components (including for example the integrated circuitsmentioned above) mounted on the board 96 is changed due to for examplechanges in the specification of the electronic device 92, therebyachieving a highly versatile cooling unit.

In plan view of the heat exchanger 76, the length direction of the heatexchanger 76 and the length direction of the tank 78 are inclined withrespect to each other, and the casing 14 is parallel to the heatexchanger 76. The heat exchanger 76, the tank 78 and the casing 14 (thecoolant supply unit 12) are accordingly efficiently disposed in alimited space, giving high space efficiency, in comparison for exampleto a structure wherein the casing 14 is disposed at an orientationinclined with respect to the heat exchanger 76 in plan view.

In particular, in the present exemplary embodiment at least one (threein the illustrated example) of the plural pumps 16 is disposed betweenthe heat exchanger 76 and the casing 14 positioned adjacent thereto.Namely, space between the heat exchanger 76 and the casing 14 is usedeffectively, with the pumps 16 efficiently disposed, giving high spaceefficiency in this respect too. Note that in a structure wherein onlyone casing 14 is present, a structure is also possible wherein thecasing 14 is disposed adjacent to the heat exchanger 76 with all of thepumps 16 disposed between the heat exchanger 76 and the casing 14 (withthe pumps 16 disposed on only one width direction side of the casing14).

Moreover, in the above exemplary embodiment, the heat receiving member74 is disposed below the casing 14 and facing the casing 14. The casing14 and the heat receiving member 74 overlap in plan view of the casing14, with the heat receiving member 74 disposed in the vicinity of thecasing 14. Space efficiency is accordingly higher than in a structurewherein the heat receiving member 74 is disposed at a position at aseparation to the casing 14. Since the distance from the casing 14 tothe heat receiving member 74 is greater in a structure wherein the heatreceiving member 74 is at a separation to the casing 14, pumps havingincrease performance per pump would be used. In the present exemplaryembodiment, there is no need to increase the performance of the pumps 16since there is a short distance from the casing 14 to the heat receivingmember 74, making it possible to achieve compact pumps 16.

FIG. 10 to FIG. 12 illustrate a coolant supply unit 112 of a secondexemplary embodiment. The cooling units in each of the followingexemplary embodiments differ from the cooling unit 72 of the firstexemplary embodiment (see FIG. 1 to FIG. 3) in the point that they eachemploy the coolant supply unit of the respective exemplary embodiment inplace of the coolant supply unit 12. Images of the overall cooling unitsare accordingly omitted from illustration in the drawings. Moreover,elements and members in each of the exemplary embodiments that aresimilar to those of the first exemplary embodiment are allocated thesame reference numerals and detailed explanation thereof is omitted. Theelectronic device 92 may be mounted with the cooling unit of any of theexemplary embodiments.

In the second exemplary embodiment, corresponding branch ports 42 andflow merging ports 44 are provided one above the other in a side wall126 of a casing 124. As can be seen from FIG. 11, the length direction(the arrow L1 direction) of respective pumps 16 is orthogonal to thelength direction (the arrow L direction) of the casing 124 in side viewof the casing 124.

In a coolant supply unit 122 of the second exemplary embodiment, theseparation between plural pumps 16 is shorter than in the coolant supplyunit 12 of the first exemplary embodiment, enabling the casing 124 to beshortened in the length direction. Note that in the second exemplaryembodiment, a distribution chamber 22 is positioned to the upper side ofa flow merging chamber 24, however the distribution chamber 22 may bepositioned below the flow merging chamber 24.

FIG. 13 to FIG. 15 illustrate a coolant supply unit 132 of a thirdexemplary embodiment. In the third exemplary embodiment, the shape of acasing 134 is substantially the same as that of the casing 124 of thesecond exemplary embodiment, however the shape of a separating wall 136differs to that of the separating wall 18 of the first exemplaryembodiment.

Namely, on a one end wall 34 side, the separating wall 136 of the thirdexemplary embodiment is bent downwards to reach a lower wall 144 so asto provide an enlarged distribution chamber 138 where a distributionchamber 22 is locally widened downwards. The enlarged distributionchamber 138 is an example of a first enlarged portion. On another endwall 36 side, the separating wall 136 is bent upwards to reach an upperwall 142 so as to provide an enlarged flow merging chamber 140 where aflow merging chamber 24 is locally widened upwards. The enlarged flowmerging chamber 140 is an example of a second enlarged portion.

In the third exemplary embodiment, the enlarged distribution chamber 138is enlarged to encompass the entire height direction of the casing 14 atthe one end wall 34 side, accordingly giving a high degree of freedomfor positioning an inlet port 30 in the height direction. The enlargedflow merging chamber 140 is also enlarged to encompass the entire heightdirection of the casing 14 at the other end wall 36 side, accordinglygiving a high degree of freedom for positioning an outlet port 32 in theheight direction.

As in the example illustrated in FIG. 16, the height of the inlet port30 and the height of the outlet port 32 may be made the same as eachother. By making the inlet port 30 and the outlet port 32 the sameheight as each other, as illustrated in FIG. 16, connection is performedeasily when plural of the coolant supply units 132 are connectedtogether in series. Installation is also easy during installation of thecooling unit provided with plural of the connected coolant supply units132 to the electronic device 92 (see FIG. 7 and FIG. 8).

Note that in a structure wherein plural of the coolant supply units areprovided to a single cooling unit, the coolant supply units may beconnected together in series as described above, or may be connectedtogether in parallel. Moreover in the third exemplary embodiment, thepositions of the distribution chamber 22 and the flow merging chamber 24may be swapped over.

FIG. 17 to FIG. 19 illustrate a coolant supply unit 152 of a fourthexemplary embodiment. In the fourth exemplary embodiment, a side wall158 of a casing 154 is alternately provided with branch ports 42 andflow merging ports 44 in a row along the casing 154 length direction(the arrow L direction). The length direction of the casing 154 (thearrow L direction) and the length direction of respective pumps 16 (thearrow L1 direction) are parallel to each other in side view of thecasing 154.

As illustrated in FIG. 18, a separating wall 156 inside the casing 154is bent at specific positions in side view. A distribution chamber 22and a flow merging chamber 24 are respectively partitioned with acorrugated pattern such that the branch ports 42 open onto thedistribution chamber 22, and the flow merging ports 44 open onto theflow merging chamber 24.

The length direction of the casing 154 and the length direction of therespective pumps 16 are thus parallel to each other in the coolantsupply unit 152 of the fourth exemplary embodiment. The height of thecasing 154 can accordingly be reduced in comparison to the coolantsupply unit 12 of the first exemplary embodiment.

The length or height of the casing 154 can be reduced by adjusting thelength direction of the casing 154 and the length direction of the pumps16. In other words, for example the coolant supply unit 12 of the firstexemplary embodiment has a structure that can be made shorter in thelength direction in comparison to the coolant supply unit 152 of thefourth exemplary embodiment. Moreover, the coolant supply unit 12 of thefirst exemplary embodiment has a structure that can be reduced in heightin comparison to the coolant supply unit 122 of the second exemplaryembodiment.

Note that in the fourth exemplary embodiment, an enlarged distributionchamber 138 is enlarged to encompass the entire height direction of thecasing 154 at a one end wall 34 side, and an enlarged flow mergingchamber 140 is enlarged to encompass the entire height direction of thecasing 154 at another end wall 36 side. There is accordingly a highdegree of freedom in the height direction for positioning an inlet port30 and an outlet port 32. For example, as in the example illustrated inFIG. 20, the height of the inlet port 30 and the height of the outletport 32 may be made the same as each other, facilitating connection whenplural of the coolant supply units 152 are connected together in series.

In the above explanation of the first exemplary embodiment an examplehas been given wherein plural of the pumps 16 are respectively disposedon both width direction sides of the casing 14. The number of pumps fora single casing 14 can accordingly be increased by providing the pumps16 on both width direction sides of the casing 14.

However, there is no requirement to have the same number of pumps onboth width direction sides of the casing 14. For example, as in acoolant supply unit 162 of a fifth exemplary embodiment illustrated inFIG. 21, the number of pumps may differ on the two width direction sidesof the casing 14. Note that the coolant supply unit 162 of the fifthexemplary embodiment has a similar structure to the coolant supply unit12 of the first exemplary embodiment except for in the respect thatthere are a different number of pumps on either width direction side ofthe casing 14.

In the second exemplary embodiment to the fourth exemplary embodiment,examples are given wherein plural pumps 16 are only disposed at onewidth direction side of the casing 124, 134, 154. The width of thecoolant supply unit can accordingly be reduced by only disposing thepumps 16 on one width direction side of the casing 124, 134, 154.

There is no requirement to connect pumps 16 to all of the branch ports42 and flow merging ports 44 even when pumps are only provided on asingle width direction side of the casing 14.

When branch ports 42 and flow merging ports 44 to which a pump 16 is notconnected are present, leading ends of the pump side connection tubes50, 52 are closed off with closing off members (see FIG. 21) such ascaps 60, to suppress unintentional coolant leakage from inside thecasing 14.

Configuration may be made wherein the casing 14 is formed with branchports 42 and flow merging ports 44 for the maximum anticipated number ofpumps 16, and provided with a sufficient number of the pumps 16 tosecure the predetermined coolant flow rate. Such a structure enables acommon casing 14 regardless of the number of pumps, thereby increasingthe versatility.

Each of the exemplary embodiments are provided with the inlet port 30through which coolant flows into the casing 14 at one end portion sideof the casing 14, and the outlet port 32 through which coolant flows outfrom the casing 14 provided at the other end portion side of the casing14. It is preferable for the pumps 16 to be provided at locationsbetween the inlet port 30 and the outlet port 32 from the perspective ofefficient coolant conveyance. Namely, each of the above exemplaryembodiments has a structure capable of securing a greater length in thecasing 14 length direction than the effective length for disposing thepumps 16.

The electronic device of embodiments discussed herein is notparticularly limited, however examples thereof include electronicdevices for which more compact and thinner design are demanded, such asdesktop or notebook (portable) computers and servers.

Explanation has been given of exemplary embodiments of technologydisclosed herein, however the technology disclosed herein is not limitedto the above, and obviously various other modifications other than thosedescribed above may be implemented within a range not departing from thespirit of technology disclosed herein.

According to the technology disclosed herein, coolant can be suppliedemploying plural pumps with a small structure.

All examples and conditional language provided herein are intended forthe pedagogical purposes of aiding the reader in understanding theinvention and the concepts contributed by the inventor to further theart, and are not to be construed as limitations to such specificallyrecited examples and conditions, nor does the organization of suchexamples in the specification relate to a showing of the superiority andinferiority of the invention. Although one or more embodiments of thepresent invention have been described in detail, it should be understoodthat the various changes, substitutions, and alterations could be madehereto without departing from the spirit and scope of the invention.

All cited documents, patent applications and technical standardsmentioned in the present specification are incorporated by reference inthe present specification to the same extent as if the individual citeddocuments, patent applications and technical standards were specificallyand individually incorporated by reference in the present specification.

What is claimed is:
 1. A coolant supply unit comprising: a plurality ofpumps; a casing that includes a coolant inlet port, a plurality ofbranch ports that respectively convey coolant to the plurality of pumps,a plurality of flow merging ports through which the coolant from theplurality of pumps merges, and a coolant outlet port; a separating wallthat is provided inside the casing and that separates the inside of thecasing into a distribution chamber that is in communication with theinlet port and the branch ports, and a flow merging chamber that is incommunication with the flow merging ports and the outlet port; a firstenlarged portion with a flow path cross-section area widened in a heightdirection at a location in the distribution chamber portion where theinlet port is provided; and a second enlarged portion with a flow pathcross-section area widened in a height direction at a location in theflow merging chamber portion where the outlet port is provided.
 2. Thecoolant supply unit of claim 1, wherein the inlet port and the outletport are provided at the same height from a bottom wall of the casing.3. The coolant supply unit of claim 1, wherein: the inlet port isprovided at one length direction end side of the casing; and the outletport is provided at the other length direction end side of the casing.4. The coolant supply unit of claim 3, wherein respective lengthdirections of the plurality of pumps intersect with the casing lengthdirection in a side view of the casing.
 5. The coolant supply unit ofclaim 3, wherein respective length directions of the plurality of pumpsare parallel to the casing length direction in a side view of thecasing.
 6. The coolant supply unit of claim 1, wherein the plurality ofpumps are provided at the casing at one side in a width directionorthogonal to a casing length direction.
 7. A coolant supply unitcomprising: a plurality of pumps; a casing that includes a coolant inletport, a plurality of branch ports that respectively convey coolant tothe plurality of pumps, a plurality of flow merging ports through whichthe coolant from the plurality of pumps merges, and a coolant outletport; a separating wall that is provided inside the casing and thatseparates the inside of the casing into a distribution chamber that isin communication with the inlet port and the branch ports, and a flowmerging chamber that is in communication with the flow merging ports andthe outlet port; wherein: a number of the plurality of branch ports isgreater than a number of pumps of the plurality of pumps, and a numberof the plurality of flow merging ports is greater than the number ofpumps of the plurality of pumps; and the coolant supply unit furthercomprises one or more closing off members that close off branch portsand flow merging ports to which the pumps are not connected.
 8. Thecoolant supply unit of claim 7, wherein: the inlet port is provided atone length direction end side of the casing; and the outlet port isprovided at the other length direction end side of the casing.
 9. Thecoolant supply unit of claim 8, wherein respective length directions ofthe plurality of pumps intersect with the casing length direction in aside view of the casing.
 10. The coolant supply unit of claim 8, whereinrespective length directions of the plurality of pumps are parallel tothe casing length direction in a side view of the casing.
 11. Thecoolant supply unit of claim 7, wherein the plurality of pumps areprovided at the casing at one side in a width direction orthogonal to acasing length direction.